Pholcus dongxue Yao & Li, 2017

Dong, Tingting, Zheng, Guo, Yao, Zhiyuan & Li, Shuqiang, 2017, Ten new species of the spider genus Pholcus Walckenaer, 1805 (Araneae, Pholcidae) from Southeast Asia, Zootaxa 4306 (3), pp. 339-369 : 363-368

Pholcus dongxue Yao & Li sp. nov.

Figs 19–20

Type material. Holotype: male (Ar29679), Charakae Cave (6°53.687′N, 99°46.743′E, elevation 25 m), La Ngu District , Satun, Thailand, 16 October 2015, Q. Zhao, G. Zhou and Z. Chen leg. Paratypes: 2 females (Ar 29680– 29681), same data as holotype.

Etymology. The specific name is a Chinese pinyin word for cave (dòng xúe), in reference to the habitat of this species; noun.

Diagnosis. The species can be easily distinguished from all known congeners in the P. yichengicus species group by the combination of the following characters: the male PME strongly protruding anteriorly (arrow in Fig. 20 F), the very short male pedipalp trochanter apophysis ( Figs 19 A–B), the absence of large dorsal sclerites subdistally on the procursus ( Fig. 19 D) and the absence of branches on the appendix ( Fig. 20 C).

Description. Male (holotype): Total length 3.56 (3.96 with clypeus), carapace 1.06 long, 1.20 wide, opisthosoma 2.50 long, 1.18 wide. Leg I: 26.4 (8.01 + 0.60 + 8.59+ 14.87+ 1.75), leg II: 19.68 (6.09 + 0.56 + 6.15 + 9.49 + 1.09), leg III: 20.18 (6.09 + 0.56 + 6.15 + 9.62 + 1.16), leg IV: 25.35 (4.81 + 0.55 + 4.10 + 6.86 + 0.90); tibia I L/d: 72. Distance PME-PME 0.34; diameter PME 0.05; distance PME-ALE 0.03; AME absent. Sternum wider than long (0.84/0.63). Habitus as in Figs 20 E–F. Carapace yellowish, with light brown marks medially; ocular area yellowish, with brown marks; sternum yellowish, with brown marks marginally. Legs yellowish, darker rings absent. Opisthosoma yellowish, without spots. Ocular area elevated, each eye triad on top of a laterally directed eye-stalk; PME strongly protruding anteriorly ( Fig. 20 G). Thoracic furrow absent. Chelicerae as in Fig. 20 D, with a pair of proximo-lateral apophyses, a pair of distal apophyses, and a pair of indistinct frontal apophyses. Pedipalps as in Figs 19 A–B; trochanter with a short ventral apophysis; femur with a distinct ventral modification; procursus simple proximally but complex distally; bulbal apophyses as in Fig. 20 C; uncus with a scaly edge; appendix curved, with a scaly edge; embolus weakly sclerotized. Retrolateral trichobothrium of tibia I at 5%; legs with short vertical setae on tibiae, metatarsi and tarsi; without spines and curved setae; tarsus I with 6 distinct pseudosegments.

Female: Similar to male, habitus as in Figs 20 H–I. Total length 3.14 (3.40 with clypeus), carapace 0.95 long, 1.06 wide, opisthosoma 2.19 long, 1.09 wide. Distance PME-PME 0.19; diameter PME 0.05; distance PME-ALE 0.02; AME absent. Sternum wider than long (0.72/0.63). Ocular area without eye-stalks; PME less protruding than male PME. Epigynum ( Fig. 20 A) with a knob. Vulva ( Fig. 20 B) with a sclerotized anterior arch and two elliptic pore plates.

Variation: Unknown (leg I lost in the other specimen).

Distribution. Thailand (Satun, type locality; Fig. 21 ).

Natural History. The species was found in the aphotic zone inside the cave.

Figures

FIGURE 19. Pholcus dongxue Yao & Li sp. nov., holotype male. A – B. Pedipalp (A. Prolateral view; B. Retrolateral view); C – D. Distal part of procursus (C. Prolateral view; D. Dorsal view). a = appendix, b = bulb, e = embolus, pr = procursus, u = uncus. Scale bars: 0.20 (A – B), 0.05 (C – D).

FIGURE 20. Pholcus dongxue Yao & Li sp. nov., holotype male (C – G) and paratype female (A – B, H – I). A. Epigynum, ventral view; B. Vulva, dorsal view; C. Bulbal apophyses, prolateral view; D. Chelicerae, frontal view; E – F, H – I. Habitus (E, H. Dorsal view; F. Lateral view; I. Ventral view). G. Ocular area, dorsal view, arrow points at strongly protruding PME anteriorly. a = appendix, da = distal apophysis, e = embolus, fa = frontal apophysis, pa = proximo-lateral apophysis, pp = pore plate, u = uncus. Scale bars: 0.05 (A – C), 0.10 (D, G), 0.50 (E – F, H – I).

FIGURE 21. Distribution records of new Pholcus species from Southeast Asia. 1. Pholcus bulacanensis Yao & Li sp. nov. from the P. bicornutus species group; 2. P. duan Yao & Li sp. nov., 3. P. ping Yao & Li sp. nov. and 4. P. vietnamensis Yao & Li sp. nov. from the P. bidentatus species group; 5. P. fuza Yao & Li sp. nov. and 6. P. mueangensis Yao & Li sp. nov. from the P. buatong species group; 7. P. cheni Yao & Li sp. nov. and 8. P. subwan Yao & Li sp. nov. from the P. halabala species group; 9. P. shuye Yao & Li sp. nov. from the P. krabi species group; 10. P. dongxue Yao & Li sp. nov. from the P. yichengicus species group.